136 G. H. Stone — Glacial Sediments of Maine. 



melting that proceeded at an equal rate throughout the whole 

 length of a long glacial river. This broadening must often 

 have been recessive, i. e., gradually extending northward. If 

 so, the broad plain that was deposited in this newly widened 

 channel was, with respect to the glacial river which to the 

 north still flowed in a narrow channel, a frontal plain. 



On the north side of hills crossed by the channels of the gla- 

 cial rivers there was a reach of water rising to the top of the 

 hill lying to the south which was in equilibrium. These hills 

 in fact formed a series of dams or lakes in the courses of the 

 rivers. The sediments deposited in these reaches of rather 

 dead water were very characteristic and the phenomenon is 

 found almost everywhere. The traces of these dams are more 

 obvious in the osar-plains than in the narrow osars. 



What are elsewhere termed narrow marine deltas appear to 

 have been deposited in channels of the ice which, if above sea 

 level, would contain osar-plains. Though narrow as com- 

 pared with the fan-shaped delta yet these channels were very 

 broad as compared with the kame and osar-channels. In 

 other words an osar-plain deposited beneath the sea became 

 the narrow marine delta. 



9. The reticulated kames. — As before stated, a plexus of 

 reticulated ridges enclosing kettle-holes is found at the land- 

 ward end of the marine and lacustrine deltas. So far the 

 reticulated ridges might be considered merely as a feature of 

 the deltas and not deserving classification as a distinct form of 

 deposit. But reticulated ridges are found unconnected with 

 deltas or only very remotely. Hence I consider them as being 

 well entitled to be recognized as a peculiar type of sedimentation. 



The plains of reticulated kames are mostly found in the 

 broader valleys and rather level regions situated between 230 

 and 600 feet above present sea-level. They are most abund^ 

 ant where the local rocks are granite, though not absent from 

 the slate areas. They are especially large and numerous in the 

 southwestern part of the State. Here they may be found ten 

 and even twenty miles in length and from one-half a mile up 

 to three or four miles in width. All degrees of complexity 

 are represented, from the great plains just mentioned down to 

 the simple case of a ridge forking into two branches which 

 after a time come together again and thus enclose a basin. 

 The plains consist of a jumble of every possible kind of ridge 

 and heap, enclosing all forms and sizes of hollows, from depres- 

 sions a foot in depth up to lake basins, which often have no 

 visible outlets. 



And not only do we find ordinary narrow kame ridges con- 

 nected by cross ridges, after the manner of the usual plexus of 

 reticulated ridges, but there are broad plains or series of reticu- 

 lated kames which anastomose over large areas and enclose 



